The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Heating and/or cooling systems, including condensing units, heat-pump systems, and other climate control systems may include a compressor, an evaporator, a condenser, and a fluid-injection system. The fluid-injection system may inject refrigerant at a pressure between suction pressure and discharge pressure (i.e., at an intermediate pressure) into an inlet of the compressor, thereby enhancing the performance of the heating and/or cooling system. The fluid-injection system may inject the intermediate-pressure refrigerant into an intermediate inlet of the compressor, which allows the compressor to compress the injected refrigerant to a discharge pressure while passing the injected refrigerant through only a portion of the compressor. While fluid-injection systems enhance system capacity, fluid-injection systems may also be employed to reduce a temperature of discharge gas exiting a compressor.